[PATCH] selftests: i915: Use struct_size() helper in kmalloc()

[PATCH] selftests: i915: Use struct_size() helper in kmalloc()

[l1138897701]

From: luoqing <luoqing@kylinos.cn>

Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows that,
in the worst scenario, could lead to heap overflows.

Signed-off-by: luoqing <luoqing@kylinos.cn>
---
 drivers/gpu/drm/i915/gem/selftests/mock_dmabuf.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/selftests/mock_dmabuf.c b/drivers/gpu/drm/i915/gem/selftests/mock_dmabuf.c
index 075657018739..5cd58e0f0dcf 100644
--- a/drivers/gpu/drm/i915/gem/selftests/mock_dmabuf.c
+++ b/drivers/gpu/drm/i915/gem/selftests/mock_dmabuf.c
@@ -103,8 +103,7 @@ static struct dma_buf *mock_dmabuf(int npages)
 	struct dma_buf *dmabuf;
 	int i;
 
-	mock = kmalloc(sizeof(*mock) + npages * sizeof(struct page *),
-		       GFP_KERNEL);
+	mock = kmalloc(struct_size(mock, pages, npages), GFP_KERNEL);
 	if (!mock)
 		return ERR_PTR(-ENOMEM);
 
-- 
2.27.0

Re: [PATCH] selftests: i915: Use struct_size() helper in kmalloc()

[Andi Shyti]

Hi luoqing,

On Sat, Feb 08, 2025 at 09:35:39AM +0800, l1138897701@163.com wrote:
> From: luoqing <luoqing@kylinos.cn>
> 
> Make use of the struct_size() helper instead of an open-coded version,
> in order to avoid any potential type mistakes or integer overflows that,
> in the worst scenario, could lead to heap overflows.
> 
> Signed-off-by: luoqing <luoqing@kylinos.cn>

Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

Thanks,
Andi

Re: [PATCH] selftests: i915: Use struct_size() helper in kmalloc()

[Andi Shyti]

Hi,

On Sat, Feb 08, 2025 at 09:35:39AM +0800, l1138897701@163.com wrote:
> From: luoqing <luoqing@kylinos.cn>
> 
> Make use of the struct_size() helper instead of an open-coded version,
> in order to avoid any potential type mistakes or integer overflows that,
> in the worst scenario, could lead to heap overflows.
> 
> Signed-off-by: luoqing <luoqing@kylinos.cn>

merged to drm-intel-gt-next.

Thanks,
Andi